diff --git a/wp-includes/rest-api.php b/wp-includes/rest-api.php
index 7b615e5a5f..99cdd3e749 100644
--- a/wp-includes/rest-api.php
+++ b/wp-includes/rest-api.php
@@ -1552,6 +1552,7 @@ function rest_stabilize_value( $value ) {
  *              Support the "minItems", "maxItems" and "uniqueItems" keywords for arrays.
  *              Validate required properties.
  * @since 5.6.0 Support the "minProperties" and "maxProperties" keywords for objects.
+ *              Support the "multipleOf" keyword for numbers and integers.
  *
  * @param mixed  $value The value to validate.
  * @param array  $args  Schema array to use for validation.
@@ -1691,9 +1692,16 @@ function rest_validate_value_from_schema( $value, $args, $param = '' ) {
 		}
 	}
 
-	if ( in_array( $args['type'], array( 'integer', 'number' ), true ) && ! is_numeric( $value ) ) {
-		/* translators: 1: Parameter, 2: Type name. */
-		return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, $args['type'] ) );
+	if ( in_array( $args['type'], array( 'integer', 'number' ), true ) ) {
+		if ( ! is_numeric( $value ) ) {
+			/* translators: 1: Parameter, 2: Type name. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, $args['type'] ) );
+		}
+
+		if ( isset( $args['multipleOf'] ) && fmod( $value, $args['multipleOf'] ) !== 0.0 ) {
+			/* translators: 1: Parameter, 2: Multiplier. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be a multiple of %2$s.' ), $param, $args['multipleOf'] ) );
+		}
 	}
 
 	if ( 'integer' === $args['type'] && ! rest_is_integer( $value ) ) {
@@ -2298,6 +2306,7 @@ function rest_get_endpoint_args_for_schema( $schema, $method = WP_REST_Server::C
 		'maximum',
 		'exclusiveMinimum',
 		'exclusiveMaximum',
+		'multipleOf',
 		'minLength',
 		'maxLength',
 		'pattern',
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 9f85ab52a5..5ba50e266c 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.6-alpha-49062';
+$wp_version = '5.6-alpha-49063';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.